1. Field of the Invention
This invention relates to the field of less or minimally invasive surgery for the purposes of revascularizing tissue. In particular, the invention relates to methods, systems, and apparatus for performing less or minimally invasive, Coronary Artery Bypass Grafting (CABG) surgery for the purposes of revascularizing tissue. Still more particularly, such systems and methods may employ conduit coupling devices. Specifically, conduit coupling devices may be used which are formed from couplers to connect conduits, such as arteries, veins, or the like, and to establish fluid communication therebetween and methods for establishing such fluid communication using such coupling devices.
2. Description of Related Art
Arteries supply tissue with nutrients and oxygen carried by blood. When arteries become diseased or obstructed, the delivery of blood to tissue may be compromised. When the tissue is denied such nutrients and oxygen, the tissue becomes ischemic and necrotic. Healthy arteries and veins may be harvested from other parts of the body and connected to diseased or obstructed vessels to bypass the diseased or obstructed portions and to restore delivery of blood to tissue, thereby reducing or preventing further tissue damage or loss. Once completed, the bypass may deliver blood flow to tissue distal to the obstruction, thereby reducing or preventing further tissue loss. When such procedures are performed on the heart, such procedures have been called CABG surgery.
Known CABG surgery methods have been performed for years by stopping the heart, placing the patient on Cardiopulmonary Bypass (CPB) apparatus, and opening the chest cavity by cutting through the ribs at the sternum. Bypass vessels then may be attached to the diseased arteries by tedious and time-consuming suturing techniques. Although the surgeon may gain the least obstructed access to the patient's heart through the ribs, i.e., by “cracking” the patient's chest, the patient's recovery may be delayed and the risk of infection and other complications associated with heart surgery may increase with such invasive techniques. Bypass suturing of this type is performed using a surgical procedure in which the chest wall remains open, thereby exposing the heart. Because such bypass procedures may be time-consuming, a patient may be subjected to prolonged anesthesia and to the use of a CPB or other cardiopulmonary support system. Prolonged exposure of a patient to these conditions may increase the likelihood of adverse reactions including delayed recover or loss of mental faculty, stroke, or death.
As noted above, known surgical bypass techniques may involve the harvesting of a blood vessel from the chest wall or the leg of a patient for use as a bypass conduit. The bypass procedure involves extensive preparation of the bypass vessels; careful positioning of the bypass vessels at the bypass site; and meticulous suturing. The reduced size of sutures used may require the surgeon to use of optical magnification. Such bypass procedures are technically challenging with results highly dependent upon the skill of the surgeon. If the attachment point between the bypass vessel and the obstructed or diseased vessel is not aligned properly, a disturbance of the blood flow may occur, resulting in a reduction in the size of the opening between the vessels. Eventually, in such cases, the bypass opening may close, thereby further obstructing a flow of blood to tissue.
One way to reduce the time during which a patient is subjected to anesthesia and CPB or other support systems has been to develop less invasive approaches to cardiac surgery. Recently, attempts have been made to develop less invasive surgical techniques, but these techniques have met with only limited success. While the use of less invasive procedures employing access devices called “ports” has been attempted, thus far, this approach has achieved limited acceptance due to difficulties that may arise when suturing bypass vessels from a remote location through such ports.